Java Programming Language

Table of Contents

1. Java
   1. Syntax & How to use

Introduction

Java is a powerful and widely used programming language known for its platform independence, object-oriented nature, and robust libraries. It is used for a wide range of applications, from mobile apps and web applications to enterprise software and big data analytics.

Java

Syntax & How to use

Java syntax is relatively straightforward and follows a structured approach. Here's a breakdown:

Basic Structure

public class MyProgram {
    public static void main(String[] args) {
        // Your code goes here
    }
}

This structure defines a class called "MyProgram" with a "main" method, which serves as the entry point for your Java program. Within the "main" method, you write your program's logic.

Variables

int age = 25;
String name = "John Doe";

Variables store data. You declare a variable with its data type (e.g., "int" for integers, "String" for text) and a name. Use the assignment operator (=) to assign a value.

Data Types

• Primitive Types: Integers (int, long), Floating-point numbers (float, double), Characters (char), Boolean (boolean)
• Reference Types: Classes, arrays, strings

Operators

• Arithmetic Operators: +, -, *, /, %, ++, --
• Comparison Operators: ==, !=, >, <, >=, <=
• Logical Operators: && (AND), || (OR), ! (NOT)

Control Flow

• if-else Statements: Execute code based on conditions.

  if (age > 18) {
    System.out.println("You are an adult.");
  } else {
    System.out.println("You are not an adult yet.");
  }
  

• Loops: Repeat code blocks.
  • for loop: Executes a block of code a specified number of times.
  • while loop: Executes a block of code as long as a condition is true.
  • do-while loop: Similar to a while loop, but executes the block of code at least once.

Arrays

int[] numbers = {1, 2, 3, 4, 5};
String[] names = {"Alice", "Bob", "Charlie"};

Arrays store collections of data of the same type. You can access elements using their index (starting from 0).

Summary

• Java is a platform-independent, object-oriented programming language.
• It features a robust set of libraries and tools.
• Java is widely used in various domains, including web development, mobile app development, and enterprise software.
• Key concepts include variables, data types, operators, control flow, and arrays.
• Java is a powerful and versatile language with a large and active community.